The 12 kinds of books on leadership

Often when I visit bookshops and browse the shelves for new publications (and there always many) on management & leadership, I am usually disappointed. The books seem to fall into a dozen broad categories (and I already have several in each):

1. How to turn your life / new job / business around in 30 days
2. Learn how to ride a bike / lead by reading a book about it
3. The 5, 13.5 or 88 secrets of success to being a better leader
4. The manual of how to lead in 297 easy written procedures with full index
5. Leadership lessons of bloody ancient leaders or blooming marvellous present ones
6. The myway by Vranson / Cricher / Jacoka / Saint / insert new name here
7. How to whack the tribe and lose the cheese: creative recipes for success
8. HBBRNOW 79! Top hits from hip business school academics
9. Dig deep, really deep inside to find your inner dude / shaman / dervish
10. 21 crazy games to get people talking with each other, sometime
11. It worked in my business: it can work in yours too!
12. New insight (again)! From the Blankcard, Hotter & Bovey book factory

Or have I missed a category?